Rostrum (anatomy)

Crustacean: the rostrum of the shrimp Macrobrachium rosenbergii is serrated along both edges.

Insect: assassin bug piercing its prey with its rostrum

Cephalopod: the two-part beak of a giant squid

The rostrum of a bottlenose dolphin

The term rostrum (from the Latin rostrum, meaning "beak") is used for a number of unrelated structures in different groups of animals:

• In crustaceans, the rostrum is the forward extension of the carapace in front of the eyes. It is generally a rigid structure, but can be connected by a hinged joint, as seen in Leptostraca.

• Among insects, the rostrum is the name for the piercing mouthparts of the order Hemiptera. The long snout of weevils may also be called a rostrum.

• Gastropod molluscs have a rostrum or proboscis.

• Cephalopod molluscs have hard beak-like mouthparts referred to as the rostrum.

• The beak or snout of a vertebrate may be referred to as the rostrum.